The class of thermoplastic polymers is well known in the art, being particularly useful because of the property of many such polymers of being deformable at relatively low temperatures. The thermoplastics are processed by conventional techniques such as extrusion, injection molding or thermoforming into films, packaging materials or shaped articles of established utility at relatively low temperatures without undue degradation of the polymer.
This property of low temperature deformation which makes many of the thermoplastics useful does, however, preclude the use of such polymers as engineering thermoplastics where exposure to elevated temperatures is likely to be encountered. When relatively high temperature applications for thermoplastics are contemplated, it is often useful to include within the polymeric chain one or more cyclic structures which typically will serve to raise the melting point or glass transition temperature of the polymer. Nevertheless, melting points or glass transition temperature near or above 200.degree. C. are not frequently encountered in thermoplastic materials. Moreover, the processing of a number of thermoplastics which melt or soften above 200.degree. C. leads to degradation of the polymer.
Polyarylene polymers which incorporate sulfone linking groups are disclosed by Johnson et al., U.S. Pat. No. 4,103,837. The use of polysulfone polymers to produce films is shown by Jones, U.S. Pat. No. 4,008,203. Lubowitz et al. describe a cross-linked oligomer containing disulfone moieties and ether linkages in U.S. Pat. No. 4,584,364. It would yet be of advantage to provide polysulfone polymers which are thermoplastics characterized by relatively high glass transition temperatures which are processable without undue degradation.